Anticoagulant and Antithrombotic Properties in Vitro and in Vivo of a Novel Sulfated Polysaccharide from Marine Green Alga <i>Monostroma nitidum</i>

• Main Authors: Sujian Cao, Xiaoxi He, Ling Qin, Meijia He, Yajing Yang, Zhichun Liu, Wenjun Mao
• Format: Article
• Language: English
• Published: MDPI AG 2019-04-01
• Series: Marine Drugs
• Subjects: marine green algae; sulfated polysaccharide; structural characteristics; anticoagulant property; antithrombotic activity
• Online Access: https://www.mdpi.com/1660-3397/17/4/247

Sulfated polysaccharides from marine algae have high potential as promising candidates for marine drug development. In this study, a homogeneous sulfated polysaccharide from the marine green alga <i>Monostroma nitidum</i>, designated MS-1, was isolated using water extraction and anion-exchange and size-exclusion chromatography. Results of chemical and spectroscopic analyses showed that MS-1 mainly consisted of &#8594;3)-&#945;-<span style="font-variant: small-caps;">l</span>-Rha<i>p</i>-(1&#8594; and &#8594;2)-&#945;-<span style="font-variant: small-caps;">l</span>-Rha<i>p</i>-(1&#8594; residues, with additional branches consisting of 4-linked &#946;-<span style="font-variant: small-caps;">d</span>-xylose, 4-/6-linked <span style="font-variant: small-caps;">d</span>-glucose, terminal &#946;-<span style="font-variant: small-caps;">d</span>-glucuronic acid, and 3-/2-linked &#945;-<span style="font-variant: small-caps;">l</span>-rhamnose. Sulfate ester groups substituted mainly at C-2/C-4 of &#8594;3)-&#945;-<span style="font-variant: small-caps;">l</span>-Rha<i>p</i>-(1&#8594; and C-4 of &#8594;2)-&#945;-<span style="font-variant: small-caps;">l</span>-Rha<i>p</i>-(1&#8594; residues, slightly at C-2 of terminal &#946;-<span style="font-variant: small-caps;">d</span>-glucuronic residues. MS-1 exhibited strong anticoagulant activity in vitro and in vivo as evaluated by the activated partial thromboplastin time and thrombin time assays, and significantly decreased platelet aggregation. The anticoagulant activity mechanism of MS-1 was mainly attributed to strong potentiation thrombin by heparin cofactor-II, and it also hastened thrombin and coagulation factor Xa inhibitions by potentiating antithrombin-III. MS-1 possessed markedly thrombolytic activity evaluated by plasminogen activator inhibitior-1, fibrin degradation products, and D-dimer levels using rats plasma, and recanalization rate by FeCl₃-induced carotid artery thrombosis in mice. MS-1 exhibited strong antithrombotic activity in vitro and in vivo evaluated by the wet weighs and lengths of thrombus, and thrombus occlusion time by electrically-induced carotid artery thrombosis in rats. These results suggested that MS-1 could be a promising marine drug for prevention and therapy of thromboembolic disease.